In reading the discussion about the 40 Man Roster for 2011 I realized that I knew little about how these gentlemen compared to one another. There seemed to be some strong opinions about their merits, although in most cases it was not clear what the source of the opinion was. Was it stats, watching enough games to form an impression of them, or something else. For example, 2010 will be the year commented,

Diaz is far more worthy than Friday. Friday is Bixler all over again, Diaz is an absolute beast on defense.

To this Wizard Imp replied

Have you actually seen Diaz play defense?

As others have said here, he is said to have good defensive "tools" but his actual play shows no evidence of him being even an average defender. More "beastly" than a beast. You think Friday is Bixler all over again? Diaz has already shown himself to be worse than Bixler.

I, at least, was not sure. I certainly hadn't seen any of these guys play shortstop for ten games. So, I started looking around, knowing that minor league fielding statistics are even more problematic than major league ones. Below are all the major candidates' AA statistics, including Ronny Cedeno. You've seen him in action all year, and he's about an average shortstop. His career fielding percentage is 970, his career range factor is 4.26, his career UZR per 150 is -2.2 (2.9 this year), and his career OPS is 635.

So, how does Argenis Diaz look? Well, he certainly can't hit. His minor league career OPS is 663, next to last, and his hitting in AA in 2009 was dreadful, with 2010 in 2010 worse still. His fielding in AA and AAA wasn't so great either, falling below his career numbers, which are a bit inflated by insane 2007 numbers.

How does Diaz compare to Friday? Surprisingly badly, it seems. Friday had the best AA and second-best career OPS of the group. His fielding percentage as a shortstop is nothing to write home about, but his range (as measured imperfectly by (Put outs + Assists)/Games is the best of the group. He certainly looks comparable to Cedeno, although Friday mostly played second at Indy this year.

Ciriaco struggles to outhit Diaz and does not appear to field better than Friday. Chase d'Arnaud has the highest career minor league OPS of the group despite his struggles this year. These statistical measures of fielding reinforce concerns about errors and range. Jordy Mercer played only 20 games at short this year, so his AA numbers don't mean a lot (other than noting that management chose to let d'Arnaud get most of the reps at short, which may reflect a scouting appraisal). For his minor league career, he looks like the best fielder of the group and a better hitter than Diaz or Ciriaco (which is faint praise at best).

My summary is that Ronny Cedeno is looking better every minute. Based on what I see here, Friday looks like the natural candidate to be added to the 40 man roster. What do you think?